Endoscopic management of benign biliary strictures

Post-trans-arterial chemoembolization hepatic necrosis and biliary stenosis: Clinical charateristics and endoscopic approach

Liver cancer is the fifth most common tumor and the second highest death-related cancer in the world. Hepatocarcinoma (HCC) represents 90% of liver cancers. According to the Barcelona Clinic Liver Cancer group, different treatment options could be offered to patients in consideration of tumor burden, liver function, patient performance status and biochemical marker serum concentration such as alpha-fetoprotein. Trans-arterial chemoembolization (TACE) is the treatment of choice in patients with diagnosis of unresectable HCC not eligible for liver transplantation, and preserved arterial supply. TACE is known to be safe and its complications are generally mild such as post-TACE syndrome, a self-resolving adverse event that occurs in about 90% of patients after the procedure. However, albeit rarely, more severe adverse events such as biloma, sepsis, hepatic failure, chemoagents induced toxicities, and post-TACE liver necrosis can occur. A prompt diagnosis of these clinical conditions is fundamental to prevent further complications. As a result, biliary stenosis could be a rare post-TACE necrosis complication and can be difficult to manage. Complications from untreated biliary strictures include recurring infections, jaundice, chronic cholestasis, and secondary biliary cirrhosis.

The utility of self-expanding metal stents in benign biliary strictures- a retrospective case series

BACKGROUND

Benign biliary strictures can have a significant negative impact on patient quality of life. There are several modalities which can be utilized with the goal of stricture resolution. These techniques include balloon dilatation, placement of multiple plastic stents and more recently, the use of metal stents. The aim of this study was to evaluate the local success of self-expanding metal stents in successfully resolving benign biliary strictures.

METHODS

This was a single institution, retrospective case series. Patients included in our study were patients who underwent endoscopic retrograde cholangiopancreatography with placement of self expanding metal stents for benign biliary strictures at our institution between 2016-2022. Patients were excluded for the following: malignant stricture, and inability to successfully place metal stent. Data was evaluated using two-sided t-test with 95% confidence interval.

RESULTS

A total of 31 patients underwent placement of 43 self-expanding metal stents and met inclusion criteria. Mean age of patients was 59 ± 10 years, and were largely male (74.2% vs. 25.8%). Most strictures were anastomotic stricture post liver transplant (87.1%), while the remainder were secondary to chronic pancreatitis (12.9%). Complications of stent placement included cholangitis (18.6%), pancreatitis (2.3%), stent migration (20.9%), and inability to retrieve stent (4.7%). There was successful stricture resolution in 73.5% of patients with anastomotic stricture and 33.3% of patients with stricture secondary to pancreatitis. Resolution was more likely if stent duration was > / = 180 days (73.3% vs. 44.4%, p < 0.05). There was no demonstrated added benefit when stent duration was > / = 365 days (75% vs. 60.9%, p = 0.64).

CONCLUSIONS

This study demonstrates that self expanding metal stents are a safe and effective treatment for benign biliary strictures, with outcomes comparable to plastic stents with fewer interventions. This study indicates that the optimal duration to allow for stricture resolution is 180-365 days.

Current advances in the management of chronic pancreatitis

Chronic pancreatitis is characterized by irreversible destruction of pancreatic parenchyma and its ductal system resulting from longstanding inflammation, leading to fibrosis and scarring due to genetic, environmental, and other risk factors. The diagnosis of chronic pancreatitis is made based on a combination of clinical features and characteristic findings on computed tomography or magnetic resonance imaging. Abdominal pain is the most common symptom of chronic pancreatitis. The main aim of treatment is to relieve symptoms, prevent disease progression, and manage complications related to chronic pancreatitis. Patients who do not respond to medical treatment or not a candidate for surgical treatment are usually managed with endoscopic therapies. Endoscopic therapies help with symptoms such as abdominal pain and jaundice by decompression of pancreatic and biliary ducts. This review summarizes the risk factors, pathophysiology, diagnostic evaluation, endoscopic treatment of chronic pancreatitis, and complications. We have also reviewed recent advances in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided therapies for pancreatic duct obstruction due to stones, strictures, pancreatic divisum, and biliary strictures.

Optimal drainage of anastomosis stricture after living donor liver transplantation

BACKGROUND

Endoscopic biliary stenting (EBS) with a fully covered, self-expandable metallic stent (FC-SEMS) and plastic stent (PS) is safe and efficient for biliary anastomotic strictures (ASs) after a deceased donor liver transplantation. Limited studies have investigated the use of FC-SEMSs for biliary strictures post-living donor liver transplantation (LDLT). We compared the resolution rate of biliary ASs post-LDLT and the 12-month recurrence rates post-stent removal between EBS with an FC-SEMS, PS, and percutaneous transhepatic biliary drainage (PTBD).

METHODS

Patients with biliary ASs after an LDLT (mean age: 57.3 years, 76.1% men) hospitalized between 2014 and 2017 were enrolled. Endoscopic retrograde cholangiopancreatography (ERCP) was repeated every 3-4 months. Patients were followed-up for at least 1-year post-stent removal.

RESULTS

Of the 75 patients enrolled, 16, 20, and 39 underwent EBS with an FC-SEMS, PS, and PTBD, respectively. Median follow-up period was 39.2 months. Fewer ERCP procedures were needed in the FC-SEMS group than in the PS group (median, 2 vs. 3; P = 0.20). Median stent indwelling periods were 4.7, 9.3, and 5.4 months in the FC-SEMS, PS, and PTBD groups, respectively (P = 0.006). The functional resolution rate was lower in the PS group (16/20) than in the FC-SEMS (16/16) or PTBD (39/39) group (P = 0.005). The radiologic resolution rate was higher in the FC-SEMS group (16/16) than in the PS group (14/20) (P = 0.07). The 12-month recurrence rates showed no significant differences (FC-SEMS, 4/16; PS, 3/16; PTBD, 6/39; P = 0.66). The rates of complications during treatment differed significantly between the groups (P = 0.04). Stent migration occurred in 1 (6.3%) and 5 (25.0%) patients in the FC-SEMS and PS groups, respectively (P = 0.59).

CONCLUSIONS

EBS with an FC-SEMS is comparable with EBS with a PS or PTBD in terms of biliary stricture resolution and 12-month recurrence rates. The use of FC-SEMSs is potentially effective and safe for biliary AS resolution after LDLT.

Establishment of a Swine Benign Biliary Stricture Model of Endobiliary Thermal Injury With a Diathermic Sheath

BACKGROUND

A reliable large animal model of benign biliary stricture (BBS) is essential to study endoscopic management of BBS. The aim of this study was to establish a swine BBS model of endobiliary electrothermal injury with a diathermic sheath and screen out the optimal energy dose.

MATERIALS AND METHODS

Twelve swine were equally randomized into a low (20 W), a medium (30 W), and a high (40 W)-dose group. Endobiliary electrothermal injury was applied to the common bile duct using a diathermic sheath at different energy doses for 20 seconds via endoscopic retrograde cholangiopancreatography. Cholangiographic findings and liver function were evaluated weekly after thermal injury. Two animals from each group were sacrificed at 2 weeks and the other 2 sacrificed 4 weeks after thermal injury for histopathologic evaluation.

RESULTS

BBS was established successfully in 10 of the 12 animals. Two of the 4 animals in low-dose group did not produce biliary stricture at 4 weeks; in medium-dose group, BBS was induced in both animals at 2 weeks without causing severe complications; and in high-dose group, BBS was produced in 4 animals at 2 weeks, causing perforation and abdominal abscess formation in 1 animal.

CONCLUSIONS

A safe and reproducible swine model of BBS could be established successfully by applying endobiliary electrothermal injury with a diathermic sheath at 30 W for 20 seconds.

The Status of SEMS Versus Plastic Stents for Benign Biliary Strictures

PURPOSE OF REVIEW

Benign biliary strictures can be treated with plastic stents and self-expandable metal stents (SEMS). This review article delineates the latest scientific evidence for their usage.

RECENT FINDINGS

Despite evolving literature on both type of stents as treatment modalities of benign biliary strictures, which encompass mainly anastomotic strictures and strictures related to chronic pancreatitis, no final conclusions can be drawn regarding the superiority of a particular stent. SEMS tend to have higher stricture resolution rates and fewer procedural requirements which are partly offset by higher stent migration and stricture recurrence rates compared with plastic stents. Additional studies focusing on new SEMS types with anti-migration features as well as cost-effectiveness calculations are necessary for clinical decision-making when treating patients with benign biliary strictures.

A New Fully Covered Self-Expandable Metal Stent for the Treatment of Postsurgical Benign Biliary Strictures

BACKGROUND

Endotherapy with plastic stent (PS) placement is the main modality for treating benign biliary strictures (BBSs). Fully covered self-expandable metal stents (FCSEMSs) are being increasingly used for BBS management, with high stricture resolution. However, traditional metal tents are associated with high migration, causing treatment failure.

METHODS

We investigated the efficacy and safety of a new FCSEMS for postsurgical BBS treatment and compared these parameters between the FCSEMS and PS treatment through retrospective analysis. The primary outcome measurements included stricture resolution, stricture recurrence, and complications.

RESULTS

In total, 69 patients were included, of whom 32 underwent FCSEMS treatment and 37 underwent PS treatment. The technical success rate and the number of endoscopic retrograde cholangiopancreatography procedures were similar between the groups. The median stenting duration was 5.2 months (range 1.5-15.3) in the FCSEMS group and 10.7 months (range 2.5-22.6) in the PS group (P < 0.01). The stents removal rate was 96.9% in the FCSEMS group and 94.6% in the PS group. The stricture resolution rate based on intention-to-treat analysis was 83.8% in the PS group and 84.4% (27/32) in the FCSEMS group (P = 0.947), whereas the rates from per-protocol analysis were 88.6% (31/35) and 87.1% (27/31), respectively (P = 0.574). Early and late complications were similar between the groups. The median follow-up time was 43 months (range 13-71). The stricture recurrence rate was 11.1% (3/27) in the FCSEMS group and 16.1% (5/31) in the PS group (P = 0.435).

CONCLUSIONS

The new FCSEMS and the PS approach showed similar efficacy and safety in postsurgical BBS treatment. However, the FCSEMS required fewer procedural steps and shorter stenting time, making it an effective alternative modality.

Benign Biliary Strictures

Differentiating benign and malignant biliary strictures is a challenging and important clinical scenario. The typical presentation is indolent and involves elevation of liver enzymes, constitutional symptoms, and obstructive jaundice with or without superimposed or recurrent cholangitis. While overall the most common causes of biliary strictures are malignant, including cholangiocarcinoma and pancreatic adenocarcinoma, benign strictures encompass a wide spectrum of etiologies including iatrogenic, autoimmune, infectious, inflammatory, and congenital. Imaging plays a crucial role in evaluating strictures, characterizing their extent, and providing clues to the ultimate source of biliary obstruction. While ultrasound is a good screening tool for biliary ductal dilatation, it is limited by a poor negative predictive value. Magnetic resonance cholangiopancreatography is more than 95% sensitive and specific for detecting biliary strictures with the benefit of precise anatomic localization. Other commonly employed imaging modalities include endoscopic retrograde cholangiopancreatography with endoscopic ultrasound, contrast-enhanced CT, and cholangiography. First-line treatment of benign biliary strictures is endoscopic dilation and stenting. In patients with anatomy that precludes endoscopic cannulation, percutaneous biliary drain insertion and balloon dilation is preferred.

Development of a Swine Benign Biliary Stricture Model Using Endoscopic Biliary Radiofrequency Ablation

The large animal model with benign biliary stricture (BBS) is essential to undergo experiment on developing new devices and endoscopic treatment. This study conducted to establish a clinically relevant porcine BBS model by means of endobiliary radiofrequency ablation (RFA). Endoscopic retrograde cholangiography (ERC) was performed on 12 swine. The animals were allocated to three groups (60, 80, and 100 W) according to the electrical power level of RFA electrode. Endobiliary RFA was applied to the common bile duct for 60 seconds using an RFA catheter that was endoscopically inserted. ERC was repeated two and four weeks, respectively, after the RFA to identify BBS. After the strictures were identified, histologic evaluations were performed. On the follow-up ERC two weeks after the procedure, a segmental bile duct stricture was observed in all animals. On microscopic examination, severe periductal fibrosis and luminal obliteration with transmural inflammation were demonstrated. Bile duct perforations occurred in two pigs (100 W, n = 1; 80 W, n = 1) but there were no major complications in the 60 W group. The application of endobiliary RFA with 60 W electrical power resulted in a safe and reproducible swine model of BBS.

Role of endoscopic retrograde cholangiopancreatography in the management of benign biliary strictures: What’s new?

Benign biliary strictures comprise a heterogeneous group of diseases. The most common strictures amenable to endoscopic treatment are post-cholecystectomy, post-liver transplantation, related to primary sclerosing cholangitis and to chronic pancreatitis. Endoscopic treatment of benign biliary strictures is widely used as first line therapy, since it is effective, safe, noninvasive and repeatable. Endoscopic techniques currently used are dilation, multiple plastic stents insertion and fully covered self-expandable metal stents. The main indication for dilation alone is primary sclerosing cholangitis related strictures. In the vast majority of the remaining cases, temporary placement of multiple plastic stents with/without dilation is considered the treatment of choice. Although this approach is effective, it requires multiple endoscopic sessions due to the short duration of stent patency. Fully covered self-expandable metal stents appear as a good alternative to plastic stents, since they have an increased radial diameter, longer stent patency, easier insertion technique and similar efficacy. Recent advances in endoscopic technique and various devices have allowed successful treatment in most cases. The development of novel endoscopic techniques and devices is still ongoing.

Endoscopic management of benign biliary strictures

Endoscopic management of biliary obstruction has evolved tremendously since the introduction of flexible fiberoptic endoscopes over 50 years ago. For the last several decades, endoscopic retrograde cholangiopancreatography (ERCP) has become established as the mainstay for definitively diagnosing and relieving biliary obstruction. In addition, and more recently, endoscopic ultrasonography (EUS) has gained increasing favor as an auxiliary diagnostic and therapeutic modality in facilitating decompression of the biliary tree. Here, we provide a review of the current and continually evolving role of gastrointestinal endoscopy, including both ERCP and EUS, in the management of biliary obstruction with a focus on benign biliary strictures.

Endoscopic management of benign biliary strictures

Benign biliary strictures are a common indication for endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic management has evolved over the last 2 decades as the current standard of care. The most common etiologies of strictures encountered are following surgery and those related to chronic pancreatitis. High-quality cross-sectional imaging provides a road map for endoscopic management. Currently, sequential placement of multiple plastic biliary stents represents the preferred approach. There is an increasing role for the treatment of these strictures using covered metal stents, but due to conflicting reports of efficacies as well as cost and complications, this approach should only be entertained following careful consideration. Optimal management of strictures is best achieved using a team approach with the surgeon and interventional radiologist playing an important role.

Covered self-expanding metal stents may be preferable to plastic stents in the treatment of chronic pancreatitis-related biliary strictures: a systematic review comparing 2 methods of stent therapy in benign biliary strictures

BACKGROUND

Covered self-expanding metal stents (CSEMS) are being increasingly used in the endoscopic treatment of benign biliary strictures (BBS). There is no solid evidence yet to support their routine use.

GOALS

To evaluate feasibility, success rate, and complications of CSEMS compared with multiple plastic stents (PS) in BBS in a systematic review.

STUDY

A systematic search of electronic databases (Medline, Scopus, and Embase) for studies published from 2000 to 2012 combined to hand-search of reference lists resulted 4977 articles. Out of 99 potentially relevant studies selected for full-text review, 12 CSEMS (376 patients) and 13 PS studies (570 patients) met the final inclusion criteria. A systematic review comparing the 2 methods was made using proportion meta-analysis.

RESULTS

A tendency to successful use of CSEMS in strictures related to chronic pancreatitis (CP) was shown: clinical success of 77% and 33% [95% confidence interval (CI), 61%-94% vs. 4%-63%, P=0.06] was achieved with CSEMS and PS at 12 months follow-up, respectively. There were no differences in the success rates of other etiologies except CP or in the early complications. In CSEMS, incidence of late adverse events was lower in CP-related strictures (3% vs. 67%, 95% CI, 0%-13% vs. 17%-99%, P=0.02). The median number of endoscopic retrograde cholangiopancreatographies was lower with CSEMSs: 1.5 versus 3.9 (P=0.002).

CONCLUSIONS

Improved clinical success with fewer endoscopic sessions and corresponding complication rate may be achieved with CSEMS treatment compared with PS in BBS secondary to CP. In other BBS etiologies, this systematic review remains inconclusive.

Successful management of benign biliary strictures with fully covered self-expanding metal stents

BACKGROUND & AIMS

Fully covered self-expanding metal stents (FCSEMS) are gaining acceptance for the treatment of benign biliary strictures. We performed a large prospective multinational study to study the ability to remove these stents after extended indwell and the frequency and durability of stricture resolution.

METHODS

In a nonrandomized study at 13 centers in 11 countries, 187 patients with benign biliary strictures received FCSEMS. Removal was scheduled at 10-12 months for patients with chronic pancreatitis or cholecystectomy and at 4-6 months for patients who received liver transplants. The primary outcome measure was removal success, defined as either scheduled endoscopic removal of the stent with no removal-related serious adverse events or spontaneous stent passage without the need for immediate restenting.

RESULTS

Endoscopic removal of FCSEMS was not performed for 10 patients because of death (from unrelated causes), withdrawal of consent, or switch to palliative treatment. For the remaining 177 patients, removal success was accomplished in 74.6% (95% confidence interval [CI], 67.5%-80.8%). Removal success was more frequent in the chronic pancreatitis group (80.5%) than in the liver transplantation (63.4%) or cholecystectomy (61.1%) groups (P = .017). FCSEMS were removed by endoscopy from all patients in whom this procedure was attempted. Stricture resolution without restenting upon FCSEMS removal occurred in 76.3% of patients (95% CI, 69.3%-82.3%). The rate of resolution was lower in patients with FCSEMS migration (odds ratio, 0.22; 95% CI, 0.11-0.46). Over a median follow-up period of 20.3 months (interquartile range, 12.9-24.3 mo), the rate of stricture recurrence was 14.8% (95% CI, 8.2%-20.9%). Stent- or removal-related serious adverse events, most often cholangitis, occurred in 27.3% of patients. There was no stent- or removal-related mortality.

CONCLUSIONS

In a large prospective multinational study, removal success of FCSEMS after extended indwell and stricture resolution were achieved for approximately 75% of patients. ClincialTrials.gov number, NCT01014390.

Intraductal radiofrequency ablation for refractory benign biliary stricture: pilot feasibility study

BACKGROUND AND AIM

Endoscopic management of benign biliary stricture (BBS) remains challenging. There is no reported method for the amelioration of biliary fibroplasia endoscopically. We report our initial experience of radiofrequency ablation (RFA) for the management of BBS.

METHODS

Nine patients with BBS (postoperation stricture four, liver transplant three, and chronic inflammation two), seven of whom had previously unsuccessful endoscopic or percutaneous interventions, were enrolled. Intraductal bipolar RFA was delivered at power of 10 W for 90 s per stricture segment, followed by balloon dilatation with/without stent placement.

RESULTS

All patients had immediate stricture improvements after RFA. No severe adverse event occurred except for one patient with mild post-endoscopic retrograde cholangiopancreatography pancreatitis. During median (SD) follow-up duration of 12.6 (3.9) months, BBS resolution without the need for further stenting was achieved in four patients whereas two patients had stent(s) in situ waiting scheduled removal. However, one patient had stricture relapse after initial resolution, one underwent surgery, and another patient died of other cause.

CONCLUSIONS

Endobiliary RFA appears to be safe and effective for the treatment of BBS, especially for refractory cases. Further studies are warranted.